Why Cardio Is Bad For You

One of my newer clients wants to know if she should be doing cardio alongside her beginner strength training programme.

The short answer is no.

Why? Because she has just stalled on her novice progression with a 40KG squat.

This is unusual and means one of three things:
1. She’s not eating enough.
2. She’s not sleeping enough.
3. She’s not resting enough in-between sets.

A quick conversation and look at her food diary confirms she’s not eating enough (because yes, you need to eat if you’re going to get stronger!).

It’s easy to assume that in order to drop a few pounds and tone up you should eat less and run more, but here’s the thing:

Cardio is catabolic. This means it breaks things down i.e. fat (but also muscle) which why people automatically assume they should do cardio when they want to lose weight.

Strength training on the other hand is anabolic. This means it builds things up – i.e muscle.

Muscle is thermogenic, which means it requires calories just to exist, and even more to grow and move.

So let’s say you go for a run. The muscles in your legs require energy to move you forward. Some energy they make themselves and the rest they get from your fat stores.

So yes, cardio can help you to lose weight.

But what happens if you only ever do cardio? You break down some fat but you also break down your muscle and the less muscle you have the less fat is used as energy.

So what happens when you do strength training? You build up muscle which requires more energy, which burns more fat.

If my client starts to do cardio now she will be working against the muscle building process and actually make it harder to burn fat in the long run.

But if we get her nice and strong first and THEN introduce some cardio she will burn more calories more efficiently.

Make sense?